Small Signal Stability Constrained Optimal Dispatch of Islanded AC Microgrid

The purpose of this study is to determine optimal values of static active power droop constants of dispatchable distributed generation units in an islanded AC microgrid to simultaneously minimize the fuel cost and enhance the small signal stability of the system. Power flow solutions are used to determine quiescent operating points of the system. The nonlinear model is then linearised about the quiescent operating points to extract the small-signal linear model. Particle swarm optimization is used to determine optimal static active power droop coefficients to meet the desired objectives. Bi-objective optimization is carried out in fuzzy domain using max-min composition. The proposed method is validated by simulation studies and comparison with the controlled elitist multi-objective genetic algorithm.